PubMed Health⌕ Search

Biomedical subjects

J Strain

Publications and source records attributed to J Strain.

At least 37 records · Page 2Linked to original sources

A physiological role for Saccharomyces cerevisiae copper/zinc superoxide dismutase in copper buffering.

The copper toxicity of yeast lacking the CUP1 metallothionein is suppressed by overexpression of the CRS4 gene. We now demonstrate that CRS4 is equivalent to SOD1, encoding copper/zinc superoxide dismutase (SOD). While overexpression of SOD1 enhanced copper resistance, a deletion of SOD1, but not SOD2 (encoding manganese SOD), conferred an increased sensitivity toward copper. This role of SOD1 in copper buffering appears unrelated to its superoxide scavenging activity, since the enzyme protected against copper toxicity in anaerobic as well as aerobic conditions. The distinct roles of SOD1 in copper and oxygen radical homeostasis could also be separated genetically: the pmr1, bsd2, and ATX1 genes that suppress oxygen toxicity in sod1 mutants failed to suppress the copper sensitivity of these cells. The Saccharomyces cerevisiae SOD1 gene is transcriptionally induced by copper and the ACE1 transactivator, and we demonstrate here that this induction of SOD1 promotes protection against copper toxicity but is not needed for the SOD1-protection against oxygen free radicals. Collectively, these findings indicate that copper/zinc SOD functions in the homeostasis of copper via mechanisms distinct from superoxide scavenging.

Copper↗

Combination antithrombotic therapy in unstable rest angina and non-Q-wave infarction in nonprior aspirin users. Primary end points analysis from the ATACS trial. Antithrombotic Therapy in Acute Coronary Syndromes Research Group.

BACKGROUND: The purpose of this study was to compare combination antithrombotic therapy with aspirin plus anticoagulation versus aspirin alone, when added to conventional antianginal therapy in patients with unstable rest angina or non-Q-wave myocardial infarction who were nonprior aspirin users. METHODS AND RESULTS: Two hundred fourteen patients were randomized; 109 were randomized to receive aspirin alone (162.5 mg daily) and 105 to receive a combination of aspirin plus anticoagulation, ie, aspirin 162.5 mg daily plus heparin (activated partial thromboplastin time, two times control) followed by aspirin 162.5 mg daily plus warfarin (international normalized ratio, 2 to 3). Trial therapy was begun by 9.5 +/- 8.8 hours of qualifying pain and was continued for 12 weeks. Primary end points were recurrent angina with ECG changes, myocardial infarction, and/or death. Analysis by intention to treat of primary events at 12 weeks was performed. At 14 days, there was a significant reduction in total ischemic events in the combination group versus aspirin alone (10.5% versus 27%, P = .004). An efficacy analysis of primary events at 12 weeks also revealed a large reduction in total ischemic events in the combination group versus aspirin alone (13% versus 25%, P = .06). Bleeding complications were slightly more common with combination therapy. CONCLUSIONS: In nonprior aspirin users, combination antithrombotic therapy with aspirin plus anticoagulation significantly reduces recurrent ischemic events in the early phase of unstable angina.

Angina, Unstable↗

The problem of coping as a reason for psychiatric consultation.

To examine those patients referred to psychiatry for the "problem of coping," a structured clinical databased management system--MICRO-CARES--was employed to identify the frequency, demographic characteristics, psychiatric diagnoses, psychosocial interventions, use of psychopharmacology, number of follow-up visits, and discharge placement of these referrals. Consultations totaling 1,157 from July 1, 1988 through January 1, 1990 were divided into two groups and compared: "Not coping" (N = 456, 28.5%) and "others" (N = 701, 61%). Those with a "problem in coping" more often had no Axis I diagnosis (p = 0.001), or were described as adjustment disorders (p = 0.0001). Fewer recommendations were made for those with a coping problem, although lag time (admission date to request for consultation), number of follow-ups, and discharge placement were not significantly different between the two groups. Stepwise logistic regression analyses revealed that the aged had lesser risk for being referred with a coping problem; those who were white, had their own income, experienced greater stress prior to hospitalization (Axis IV), and had higher functioning during the last year (Axis V) were at greater risk.

Adaptation, Psychological↗

Coronary risk factors in schoolchildren.

Death rates from coronary heart disease (CHD) in Northern Ireland are among the highest in the world. However, no data have been available to test the hypothesis that the high prevalence of CHD is reflected by the risk status of the childhood population. A randomly selected 2% population sample of 1015 children aged 12 and 15 years was studied to obtain baseline information on blood pressure, lipid profile, cigarette smoking, family history, physical activity, cardiorespiratory fitness, and dietary fat intake. Using available criteria thresholds, 15-23% displayed increased blood pressure, 12-25% had unfavourable lipid profiles, and 18-34% were overfat. In 15 year old children, 16-21% admitted being regular smokers, 26-34% displayed poor cardiorespiratory fitness, and 24-29% reported little physical activity in the previous week. Dietary analysis revealed relatively low polyunsaturated to saturated fatty acid ratios and high mean fat intakes, accounting for approximately 40% total daily energy. Despite the exclusion of family history from the analysis, 16% of the older children exhibited three or more risk factors. These results justify major concern about the level of potential coronary risk in Northern Ireland schoolchildren. Broadly based primary prevention strategies aimed at children are essential if future adult CHD mortality is to be reduced.

Adolescent↗

Usefulness of the Neurobehavioral Cognitive Status Examination in the hospitalized elderly.

A prospective pilot study compared the Neurobehavioral Cognitive Status Examination (NCSE) to the Folstein Mini-Mental State Examination (MMSE) to determine the usefulness of the NCSE as a cognitive screen in a geriatric inpatient population. All patients directly admitted to the geriatric evaluation and treatment unit (GETU) of a university teaching hospital over a two-and-a-half-month period were eligible for the study, in which 42% participated. Within 72 hours of admission, patients were given the MMSE and the NCSE in a nonrandom order by a trained psychologist and a structured interview by a psychiatrist. The ability of the NCSE to detect global cognitive impairment was compared to the MMSE and psychiatrist's assessment. Differences in sensitivity were examined by discordant pair analysis. The psychiatrist's determination of the presence of cognitive impairment was used as the criterion standard. Comparisons of the MMSE and NCSE, respectively, revealed the following: sensitivity 83% versus 100%; specificity 78% versus 11%; positive predictive value 83% versus 43%; and negative predictive value 78% versus 100%. Seven patients who were cognitively impaired by the NCSE were not impaired by the MMSE (p less than 0.05 by discordant pair analysis). The time of administration for the two tests was significantly shorter for the MMSE (14.75 +/- 5.7 minutes) than for the NCSE (38.9 +/- 12.9 minutes). The NCSE was found to be more sensitive than the MMSE in detecting cognitive impairment among geriatric inpatients, but its specificity and positive predictive values were lower. Beyond this pilot study, additional work examining the utility of the NCSE in other geriatric settings and for different purposes (e.g., as part of comprehensive assessment) needs to be performed.

Aged↗

Using patient reports to assess hospital treatment of persons with AIDS: a pilot study.

Providing efficacious, compassionate, and efficient medical care to persons with HIV infection is one of the greatest challenges that will face US hospitals this decade. Unfortunately, there have been almost no studies of how organizational arrangements are related to the quality of care. We developed an interview protocol and conducted a pilot study to evaluate the instrument's ability to detect differences in selected interpersonal aspects of care provided to persons with AIDS. We evaluated the care received in two different treatment models in a major teaching hospital: a designated AIDS unit and general medical beds. We assessed several areas of patient care that are clinically important and that patients can evaluate: communication between patients and providers, patient education, respect for patient preferences, emotional support, involvement of family and friends, trust and confidence, physical care, pain management, AIDS knowledge, perceived segregation, confidentiality, and financial information. Patients generally were very satisfied with their hospital care, but many reported problems with certain aspects of their care. The instrument used detected differences between the care reported by patients treated in general hospital beds and in a designated AIDS unit in several specific aspects of care.

Acquired Immunodeficiency Syndrome↗

Adjustment disorder in children and adolescents.

The literature on adjustment disorder in children and adolescents is reviewed to evaluate the empirical and conceptual basis of this disorder as defined in DSM-III-R, and to determine whether revisions, are indicated in DSM-IV. Existing studies suggest that adjustment disorder is a disorder of high prevalence in all settings, which carries significant morbidity and poor outcome in children and adolescents. Problems identified with the DSM-III-R definition include low reliability, the predominance of mixed rather than discrete symptom presentations in children and adolescents, and the persistence of symptoms in excess of 6 months in a significant number of cases.

Adjustment Disorders↗

The inpatient AIDS unit: a preliminary empirical investigation of access, economic, and outcome issues.

An AIDS unit model ("cluster beds") and a general inpatient placement model ("scatter beds") in a major teaching hospital were compared to determine whether they differed on several dimensions of care. After controlling for severity of illness, (the major predictor of admission to the AIDS unit), length of stay, charges, and inpatient mortality rates did not differ between the two settings. Equal proportions of White, Hispanic, male, and privately insured patients were found in both settings. Nursing staff turnover rates were comparable to those of other sites. However, the data raise new issues regarding access to AIDS units for older, Black, and female patients.

Acquired Immunodeficiency Syndrome↗

Adipose dysplasia of the right ventricle: is endomyocardial biopsy useful?

Right ventricular dysplasia (RVD) is a cardiac anomaly characterized by replacement of right ventricular myocardium by adipose and fibrous tissue that was first described at autopsy, and is now being recognized pre-mortem. Sudden death and ventricular arrhythmias are the most common clinical manifestation of the condition. This paper reviews the literature on myocardial biopsies performed in patients with idiopathic arrhythmias who had pathologic findings consistent with RVD, and the results of biopsies from patients suspected of having RVD. The significance of sampling error in myocardial biopsies, possible familial associations, and other conditions associated with myocardial adipose infiltration are also discussed. Based on the review, the possibility is raised that RVD may represent the end result of an unusual healing process, whereby genetically susceptible individuals recover from a variety of RV insults by deposition of adipose tissue. These fatty scars may then be the focus for arrhythmias which remain the major clinical manifestation of the syndrome.

Adipose Tissue↗

Angiographic and hemodynamic correlations in hypertrophic cardiomyopathy with intracavitary systolic pressure gradients.

To correlate angiographic and hemodynamic events in hypertrophic cardiomyopathy (HC), 14 patients with HC were investigated using pressure recordings and caudocranial left anterior oblique contrast angiography. Patients were separated into 2 groups on the basis of the presence (group I) or absence (group II) of systolic anterior motion of the anterior mitral leaflet on caudocranial angiography. In group I (10 patients), the pressure gradient could be recorded with the left ventricular (LV) catheter in the nonobliterated inflow region of the left ventricle. Simultaneous micromanometer tracings and caudocranial angiography revealed that contact between the anterior mitral leaflet and the ventricular septum was an early systolic event (occurring 136 +/- 33 ms after the R wave of the electrocardiogram) and was coincident with the onset of the pressure gradient. Cavitary obliteration was present in only 7 of 10 patients in group I, and occurred late in systole well after the peak gradient (292 +/- 28 ms after the R wave). In group II (4 patients), the pressure gradients could be recorded only from the obliterated portion of the ventricle distal to the level of the papillary muscles. Total LV cavitary obliteration was present in all group II patients. In 1 patient, simultaneous micromanometer pressure recording and caudocranial angiography revealed that cavitary obliteration preceded the peak gradient by 40 ms. Thus, in group I patients the onset of the pressure gradient is coincident with mitral leaflet-septal contact, while cavitary obliteration is an inconsistent late systolic event.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗

Systemic and coronary effects of intravenous milrinone and dobutamine in congestive heart failure.

The effects of dobutamine and intravenous milrinone on systemic hemodynamics, coronary blood flow and myocardial metabolism were studied in 11 patients with severe congestive heart failure. Although milrinone and dobutamine similarly increased cardiac index from 1.9 +/- 0.4 to 2.5 +/- 0.4 liters/min per m2 (p less than 0.001) and from 1.9 +/- 0.4 to 2.8 +/- 0.8 liters/min per m2 (p less than 0.001), respectively, milrinone decreased left ventricular end-diastolic pressure to a greater extent than dobutamine, that is, from 26 +/- 6 to 12 +/- 8 mm Hg (p less than 0.001) versus 26 +/- 8 to 20 +/- 8 mm Hg (p less than 0.001). In contrast to dobutamine, milrinone significantly reduced mean systemic arterial and right atrial pressures. Dobutamine increased the first derivative of left ventricular pressure (dP/dt) from 1,013 +/- 309 to 1,360 +/- 538 mm Hg/s (p less than 0.01) but milrinone did not. Similarly, blood flow and myocardial oxygen consumption were increased by dobutamine from 152 +/- 87 to 187 +/- 118 ml/min (p less than 0.05) and from 17.7 +/- 10.9 to 21.5 +/- 14.9 ml O2/min (p less than 0.05), respectively, but were unchanged by milrinone. Both drugs significantly decreased coronary vascular resistance and myocardial oxygen extraction but did not change myocardial lactate extraction. Thus, dobutamine and milrinone produce similar improvement in cardiac index. However, dobutamine increases myocardial oxygen consumption, whereas milrinone does not. This difference can probably be explained by the substantial vasodilating properties of milrinone.

Aged↗

Effects of milrinone on left ventricular performance and myocardial contractility in patients with severe heart failure.

The potent vasodilating properties of the bipyridine derivatives confounds the assessment of changes in contractility as measured by peak positive left ventricular dP/dt and explains why the positive inotropic action of these agents has not been consistently demonstrated in patients with ventricular dysfunction. Therefore we studied the individual dose-response effects of intravenous milrinone on myocardial contractility as measured by peak positive left ventricular dP/dt in the context of concurrent changes in ventricular filling pressure. Incremental doses of milrinone caused a dose-related increase in peak positive left ventricular dP/dt in six of 11 patients. Peak positive left ventricular dP/dt was unchanged in four patients and reduced in one patient, all of whom experienced a substantial fall in left ventricular filling pressure. Thus milrinone has a definite inotropic effect in addition to its potent vasodilating properties.

Animals↗

Effects of a new cardiotonic agent, MDL-17,043, on myocardial contractility and left ventricular performance in congestive heart failure.

MDL-17,043, a newly synthesized imidazole derivative, has been shown to manifest both inotropic and peripheral vasodilating properties in experimental animals and to be effective when administered orally. Although MDL-17,043 has been demonstrated to inhibit cyclic adenosine monophosphate (AMP) phosphodiesterase activity in vitro, whether its inotropic activity derives from increased myocellular levels of cyclic AMP is not yet known. After intravenous administration of MDL-17,043 to seven patients with severe congestive heart failure (CHF) at the time of cardiac catheterization, the rate of left ventricular (LV) pressure rise increased almost immediately from a control of 878 +/- 161 to a peak of 1010 +/- 217 mm Hg/sec (p less than 0.01), while cardiac index tended to increase but not significantly. Subsequently, as mean aortic pressure decreased from 86.4 +/- 15.9 at control to 75.6 +/- 16.4 mm Hg (p less than 0.01), cardiac index rose from 1.87 +/- 0.35 at control to 2.30 +/- 0.27 L/min/m2 at peak effect (p less than 0.01), while pulmonary capillary wedge pressure fell from 23.7 +/- 5.1 to 13.1 +/- 4.6 mm Hg (p less than 0.01). Concomitantly, the rate of LV pressure rise returned to control value. Thus, intravenous administration of MDL-17,043 improves myocardial contractility and LV performance in patients with severe CHF. This manifest improvement in LV performance most probably results from both the positive inotropic and direct vasodilating effects of MDL-17,043.

Cardiotonic Agents↗

Pulmonary arterial V waves in mitral regurgitation: clinical and experimental observations.

Pulmonary arterial early diastolic waves (V waves) were investigated in patients and experimental animals with mitral regurgitation. V waves exceeding systolic pressure in the pulmonary artery were recorded in the main pulmonary artery with micromanometer catheters both in patients and animals, eliminating the possibility of catheter artifact. In experimental animals, aortic closure preceded pulmonic closure by 33 +/- 12 msec at baseline. With the creation of acute mitral insufficiency, a pulmonary arterial V wave occurred in six of eight animals. Early pulmonic valve closure occurred only in the six animals with a pulmonary arterial V wave. In these animals, pulmonic closure preceded aortic closure by 28 +/- 7 msec during mitral insufficiency (p less than .05). Of 70 patients with severe mitral regurgitation at cardiac catheterization, 14 had a pulmonary arterial V wave. In five patients recordings with micromanometer catheters were made and early pulmonic closure was also observed in four of these patients who had pulmonary arterial V waves at rest or upon provocation. Patients with pulmonary arterial V waves had a more acute onset of symptoms, shorter duration of mitral regurgitation, higher pulmonary capillary wedge V waves, and lower pulmonary arterial resistances than patients without them and were more likely to have nonrheumatic mitral regurgitation.

Adult↗

Right ventricular function in valvular heart disease: relation to pulmonary artery pressure.

Right ventricular angiography was performed in 46 patients with acquired valvular heart disease and 8 normal subjects. Right ventricular ejection fraction (RVEF) correlated highly only with right ventricular peak systolic pressure (RVPSP) and mean pulmonary artery pressure, both in patients with and without tricuspid insufficiency. For the group, RVEF = -0.33 RVPSP + 63 (correlation coefficient [r] = -0.76, probability [p] less than 0.001). Of 20 patients with moderate or severe elevation of pulmonary artery pressure, 17 (85%) had an abnormally low ejection fraction (less than 47%), while 19 (73%) of 26 patients with normal or mildly elevated pulmonary artery pressure had a normal right ventricular ejection fraction. In seven patients with elevated pulmonary artery pressure, a second ventriculogram was performed during intravenous nitroglycerin administration. Nitroglycerin produced a significant decrease in right ventricular peak systolic pressure (59 +/- 22 to 49 +/- 18 mm Hg, mean +/- standard deviation) (p less than 0.05) and in end-systolic volume (71 +/- 16 to 59 +/- 11 m1/m2) (p less than 0.05), and an increase in ejection fraction (43 +/- 9 to 48 +/- 7%) (p less than 0.05). Thus, at least part of the depression of ejection fraction in patients with elevated pulmonary pressure is reversible with a decrease in pulmonary artery pressure.

Adult↗